Facepiece



Feb. 1947- w. J. S'HARBAUGH ETAL 1 FACE E cE Filed April 10,1942 2 Sheets-sheaf. 1.

I INVENTORS WILLIAM J. SHHRBAUGH YANT '1" v I BY WILLIAyL/Z ATTORNEY.

Feb. 25,1947- w. J. SHARBAUGH ETAL 2,415,411

FACE PIECE Filed April 10. 1942 2 Sheets-Sheet? M M P YHNT Arm/max.

INVENTORS SHRR BAUGH Patented Feb. 25, 1947' William J Sharbaugh, Wilkinsburg, and William P. Yant, Murraysville, Pa., assignors to Mine Safety Appliances Company, Pittsburgh, Pa.

Application April 10, 1942, Serial No. 438,378 7 This invention relates to an improvement in a facepiece used as a part of breathing apparatus, and more particularly, to a construction adaptable for use atlow temperatures and constitutes an improvement of .the facepiece as described in an application of William P. Yant for Letters Patent Serial No. 422,791, filed December 13, 1941. The type of apparatus for which this facepiece is especially adaptable is the demand type of apparatus in which the facepiece is connected to a source of respirable air and in which is interposed a regulator responsive to the differences in pressure in the respiration cycle to control the flow of air to the facepiece and in which the air discharged in exhalation is eliminated from the facepiece by means of exhalation valves.

Since this type of apparatus is used at high altitudes and extremely low temperatures, considerable diificulty is had in preventing the exhalation valves from freezing because theexhaled air contains considerable moisture and rapidly condenses about the exhalation valve which freezes and prevents the functioning of the valve forcontrolling the discharging of'air from the facepiece. Another factor of importance constituting a material disadvantage to the old constructions is that air passing into-the facepiece from'the supply is at such low temperature that it causes great discomfort and sometimes injury to the nasal passages and respiratory system.

It is among the objects of this invention to provide a facepiece arranged to enclose the nose and mouth from the atmosphere and having means operative to warm the respirable air entering the facepiece from the heat given off by the wearer, and which also includes a mounting, integral with the facepiece in each side portion, for an exhalation valve that protects the valve from being subjected to the extreme temperatures encountered and makes available heat withinthe facepiece for eliminating some freezing about the valve, and which is simple in construction and relatively inexpensive to manufacture. v

Other objects of this invention will becom apparent from a description of a preferred embodiment of the improvement which incorporatesthe principles of the invention and which is illustrated in the drawings, in which: 1

Fig. 1 is an elevational view of the preferred embodiment of the invention and illustrates the assembly of a facepiece incorporating the invention to an aviatorshelmet;

Fig. 2 is a sectional view taken centrally of the facepiece along the line 2--2 of Fig. 4; s

Fig. 3 is a top plan view of the facepiece part- 4 Claims. (Cl. 128-146) ly in section illustrating the mounting of an exhalation valve to the improved facepiece;

'Figs. 4, 5 and 6 are front, side and rear elevational views, respectively, of the embodiment; Fig. '7 is a sectional view of the exhalation valve taken along the lines 1-1 of Fig. 6; and

, Fig. 8 is asectional view taken along the line 8-8 of Fig. 2,

Th facepiece I is made of a moldable material shaped to conform to the outlines of the face and suiliciently concave to accommodate the nose and mouth and to allow for a small chamber in front of the facepiece to operate as a breathing chamois has been successfully used. This lip is usually contoured to conform as nearly as possible to the face and yet possess some yieldability so that, its contour maybe altered to conform to the differences in features of wearers as well as apply 'a slight sealing pressure to the face when worn to provide an adequate seal. The lip has a lower portion 3 that extends into the cavity toward the front of the facepiece and op- Zerates as a chin stop portion. As illustrated in Fig. 2, thisportion 3-is arranged to be in spaced relation to the inner underside surface of the chin portion lb of the f'acepiece. The portion lb extends well under the chin toward the neck and forms an air chamber 5 in combination with the chin stop portion 3 of the lip. This chamber is "is transmitted from other portions of the face.

An inlet duct 6 connected to the source of respirable air is integrally molded to the faceplece and forms a part of the body.

In order to direct the flow of respirable air passing to the facepiece through the inlet duct 6 into this warmin'g'chamber 5 before flowing upwardly tothe respiratory organs of the wearer, a system of baffles is provided. To acc m-' ing. 7

- 3 plish this, a baflle 8, Figs. 2, 6 and 8 is provided which extends across the inlet duct in spaced relation to the juncture of the inlet tube and the facepiece and upwardly into the inner cavity of the facepiece. This baffle directs the air upwardly against another bafile 9 positioned with relation to'the chamber!) and the baffle 8 so that it receives the air directed upwardly by the baffle 8 and diverts it into the chamber 5. This bafile 9 is located at about the juncture of the inlet duct to the facepiece at its uppervextrem- V ity, Fig. 2, and extends downwardly and somewhat rearwardly into the cavity of the facepiece to provide the directing face which engages the air forced upwardly in the duct by the baffle 8. Although air entering the facepiece from the duct 6 through the chamber is not heated to a considerable extent, the amount of heat transferred is sufficient to measurably relieve the discomfort of breathing'air direct from the inlet duct. The additional passage doesnot impose any appreciable resistance to the flow of air for breathing and, in fact, the increase in resistance is not enough to show in tests conducted to determine if any'exists. This is due to the excess area of the duct and passage in the facepiece provided for the flow required for respiration. I

For discharging exhaled air from the facepiece, openings Id are provided in the side portions Ic.

Interposed in each of these openings is an exhalation valve I0 so arranged that during inhalation the valves are caused to seat'themselves and during exhalation the increased pressure allows air to pass into the outside atmosphere. The type of exhalation valve represented is old in the art, but the mounting provided for the exhalation valve forms a part of this invention. The material of the facepiece about each opening is molded to form a short duct Iethat extends a short distance into the concave portion of the facepiece and terminatesin a supporting flange I f that extends inwardly closing off a part of the open- The exhalation valve I0 has a housing I I that enclosesthe valve. The housing is threaded to an inner valve assembly 13 andhas aninner face I2 cooperative with an extending flange l4 of the valve assembly I3 to formagripper means for the flange if of the facepiece. A-valve Illa is seated on the assembly I3 and is movable outwardly. or

. into the housing for opening the passage and-relieving pressure in the facepiece; Suitable outlet openings Ito are providedin the valve assembly for introducing air to the valve While openings I Ia are provided in the housing I I through which the exhaled air is discharged into the atmosphere.

In mounting, the housing I I is placed on the outer side of the flange If and the valve assembly i 3 is threaded into the housing through-the flange of the duct until the flange I4 of the assembly I3 presses the flange of the duct tightly against the inner surface I2 of the housing to sealthe valve to the facepiece. The valve Elia controls movement of air through the opening in the face piece. Normally, the valve is held closed by-a spring, but the valve and spring are responsive to exhalation pressures to move the valve to an open position and discharge air through the open: ing.

To, prevent the moldable material gripped between the surfaces from being displaced, a sealing washer I6 is placed around the outer surface of the duct and flange to'give the material some rigidity and to prevent the facepiece material from working out between the gripping surfaces s d of the exhalation valve. With this mounting of the exhalation valve, the valve is disposed in the cavity of the facepiece in the duct Ie. In this position, a, certain amount of heat is conveyed to the valve to prevent freezing of the moisture that may be deposited during exhalation.

In order to further protect the valve, a, louver I! is formed integrally with the facepiece and outwardly of the facepiece body which completely encloses the outside of the valve from the atmosphere. It is arranged to completely" enclose the valve and extend rearwardly beyond the exhalation valve and terminates in an outlet I8.

Due to variations in facial size, it is advisable to include some form of an adjustable member about the nose, such as a wire 26 mounted to the body by means of lugs 2! formed integrally with the facepiece. This wire 29 is preferably positioned substantially in alignment with the inner periphery of the facepiece about the nose portion and is efiective' to hold the material against the face when brought against the nose. It is rec'- ognized that this addition of using an outer clip fastened on to thefacepiece is not new but the particular arrangement illustrated in the drawing, that is, mounting the wire member in a somewhat vertical postion and in combination with piece located in front of the mouth and of such construction that it conforms to the housing of the microphone and of such size that it is yieldable. B inserting the housing into the shaped portion, it is tightly gripped and held in position. In actual molding, the front end can be completely closed off and can be made to accommodate a wire '21 of the microphone by cutting an opening into the end and passing the wire through I this opening after the microphone has been ass'embled into this portion. As a means of holding the facepiece in-protective position, certain straps are necessary'which obtain support from the head. An improved means for attaching head straps to the facepiece and to a helmet worn by the wearer is to attach straps 28 and 29; to each side of the facepiece bymeans of button fasteners. The upper strap 28'carries a fastener 30 at its outer end which has an inwardly directed hook that engages a cooperating fastener mounted on to the hat.

' This quick attachment is advantageous in many instances where the facepiece is worn. The lower strap is attached to the helmet by means of a buckle 32. Frequently, the facepiece is mounted to the helmet by means-of the lower strap and is notbrought into operative position on the face until atmospheres are encountered which 'clemand protection measures. This means on the upper strap provides for quick and convenient as- 1 sembly to a protective position.

I'Since this facepiece is especially adaptedlfor low temperature use, it is of advantage to cover the outer surface of the body of the facepiece with some form of insulating material as sponge rubber. In one such construction, an insulating body is provided having an inner surface complewmentary to the outer surface of the body. The insulating body is attached to the body by apply,- I

ing an adhesive and heat and Dress'urefto integrally attach the insulating body to the face.

a: 1:) piece body. For some purposes, covering only the louvers I'I enclosing the exhalation valves.

with insulating material gives greater protection for the valves and insures against their freezing.

In connection with the baffle arrangement, baf-r fies 8 and 9 being interposed in the inlet to the facepiece body to deflect the air entering the facepiece to the chamber 5, the insulating layer on the outside of the facepiece body accentuates the function of the warming chamber and pro-J vides more comfort for the wearer. It is to he observed, however, that some comfort is obtained from the interposition of the bafiies due to elimination of an impingement action of entering air against the face and a material reduction in the velocity of air before inhalation by the wearer. This chamber 5, also, provides a reservoir for collection of moisture discharged in use of the facepiece. The condensate, in some instances, may freeze and to remove the face from contact with the condensate eliminates discomfort.

According to the provisions of the patent statutes, we have explained the principle and mode of operation of our invention, and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be pract ced otherwise than as specifically illustrated and described.

We claim:

1. A facepiece comprising a concave mask of protective material formed to enclose the nose and mouth and extending back under the chin, the lower portion of said mask being provided with an inlet in front of the chin, a face-engaging lip integral with the edge of the mask and extending inwardly and forwardly therefrom, the lower portion of said lip being formed to fit under and in front of the chin in contact therewith and being spaced from the bottom and front of the mask to form a gas-warming chamber under the chin, the front of said chamber opening upwardly into the mask behind said inlet, and baffle means projecting inwardly from the mask into the path of a breathing gas entering through said inlet and positioned to direct said gas into said chamber before it passes up into the mask for breath- 2. A facepiece comprising a concave mask of protective material formed to enclose the nose and mouth and extending back under the chin,

the lower portion of said mask being provided with an inlet in front of the chin, a face-engaging lip integral with the edge of the mask and extending inwardly and forwardly therefrom, the lower portion of said lip being formed to fit under and in front of the chin in contact therewith and being spaced from the bottom and front of the mask to form a gas-warming chamber under'the chin, the front of said chamber openingupwardly into the mask behind said inlet, and baffle means integral with the mask and extending transversely thereof, said means extending across the path of a breathing gas entering through said,

inlet and positioned to direct said gas in a thin wide stream into said chamber before itpasses up into the mask for breathing.

3. A facepiece comprising a concave-mask of protective material formed to enclosethe nose and mouth and extending back undercthe chin, the lower portion of said mask being provided with an inlet in front of the chin, a face-engaging lip integral with the edge of the mask and ex tending inwardly and forwardly therefrom, the lowerportion of said lip being formed to fit under and in front of the chin in contact therewith and being spaced from the bottom and front of the mask to form a gas-warming chamber under the chin, the front of said chamber opening upwardly into the mask behind said inlet, a baffle member, extending upwardly between saidinlet and chamber to deflect incoming breathing gas upwardly in front of the chamber, and another bafile member projecting rearwardly from the front of the mask across the top of said firstmentioned bafile member in closely spaced relation thereto to deflect said upflowing gas downwardly in a thin, wide stream into said chamber before it passes up into the mask for breathing. i

4. A facepiece comprising a concave mask of protective material formed to enclose the nose and mouth and extending back under the chin,

the lower portion of said mask being provided lip integral with the edge of the mask and extending inwardly and forwardly therefrom, the lower portion of said lip being formed to fit under and in front of the chin in contact therewith and being spaced from the bottom and front of the mask to form a gas-warming chamber under the chin, the front of said chamber opening upwardly into the mask behind said inlet, baffie means projecting inwardly from the mask into the path of a breathing gas entering through saidinlet and positioned to direct said gas into'said chamber before it passes up into the mask for breathing, straps connected to the opposite sides of the mask, and a hook on the rear end of each strap adapted to engage a complementary member on a helmet worn by the wearer of the facepiece.

WILLIAM J. SHARBAUGH.

WILLIAM- P. YANT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 7 Date 1,320,935 Schwartz Nov. 4, 1919 1,312,200 Patus Aug. 5, 1919 2,238,954 Benos Apr. 22, 1941 2,228,502 Bo-othby Jan. 14, 1941 1,926,027 Biggs Sept. 12, 1933 2,320,770 Cover June 1, 1943 731,973 Teter June 23, 1903 2,323,198 Bulbulian June 29, 1943 2,329,154 Bulbulian Sept. 7, 1943 FOREIGN PATENTS Number Country Date 472,536 British Sept. 24', 1937 569,708 German Feb, 7, 1933 569,355 French Jan. 6, 1924 671,175 German Feb. 1, 1939 814,973 French I Mar.30, 1937 OTHER REFERENCES Cover vs. Schwartz, 52 s. P. Q. 367; 56 U. s; 'P.Q.37.

Schwartz vs. W. S. Wilson Corp., 46 Fed. Supp. 

